VITALITY AND GERMINATION OF SEEDS. 221 



Marked fermentative changes go on in Peas kept in 

 de-oxygenated water and these are accompanied by a 

 marked evolution of bubbles of gas, the water at the same 

 time owing to the formation of organic acids, becoming 

 of distinctly acid reaction. In the water after 3 or 4 days 

 immersion traces of reducing sugar can be detected. 

 The gas evolved consists of a mixture of C0 2 and H, the 

 former being in the greater proportion. 



The fermentative changes induced in the carbohydrates 

 of the seed have therefore gone so far as the Lactic and 

 Butyric fementations and it is owing to the formation of 

 these acids that the medium becomes distinctly acid. If 

 after 10 days immersion the Peas are planted it is found 

 that they have all been killed. Oxygenless water is there- 

 fore more fatal than oxygenated water. The marked 

 fermentative changes which the former induces seem to 

 be extremely inimical to the preservation of the vitality 

 of the seeds. In water which was oxygenated to com- 

 mence with, as a consequence of the preliminary growth 

 which the radicles for the most part undergo, the latter 

 are freely exposed to the action of the Bacteria, etc., 

 contained in the stagnant water whilst the plumule is 

 protected by its position between the closely appressed 

 cotyledons. Hence in Peas which have been kept in 

 water for 5 days, the radicle is often found on germination 

 to have been killed, the plumule only developing. Thus 

 in one such experiment 75 p.c. of the seeds germinated, 

 of these 50 p.c. were normal seedlings, in 15 p.c, the 

 plumule developed normally, the tap root being aborted 

 and replaced by lateral roots, in 10 p.c. no roots at all 

 were formed, the plumule in this case dying after attaining 

 a length of a few inches or so, whilst in those seeds in 

 which the plumule was dead to commence with, the 

 vitality of the radicle was so much lowered that it was 



